SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e802505161d567babedf957642d65c1bcbe251d86325f4193bd02ccd1007dc92' 
  AND token = 'mmKKEUtvUfYCMVlCVUCowIeQ/CmhrqatVbA2mWVd1Eg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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