SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0685b210d195128b57a1c768b474ce7e953eacc3070ce4bb3a8f53b5927d5065' 
  AND token = '6oMwXYfSz57K0Fn0r05kdcIAgAEiDOXeW6ylh3yzJUo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}