SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7d482b93ddda7b8b7ceecc6821b4066db16d15f295796aa9afb8f85684e34bd9' 
  AND token = '+u6sdBO3qKfjVCgmkoii08S88CiomqER1Uq3JQQK1QM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}