SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '70fdedb707ff43ebb59db45e1ae22d4b389fe2b28da7786d3dba7d0fa96e8508' 
  AND token = 'Zr+bgRuHiEO4xGS/yV6qpYo4JU+YNTXzxSZAQSC5QvA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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