SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c2332e13dee792c244f6254f36b4d2485d46ca10e4c3afb9d966d3bc8ba4611c' 
  AND token = 'niKefv8yPwX/CFvCS376oQ/CdrzY53dhjO5gBIQxVgM=' 
  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"
    }
  }
}