SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ebc22fca0ade01136d4a424f7d5d22ec8cf6d2cbb44942de9981277c8c4fa017' 
  AND token = 's4cHgZ6PRxneXryqiluklbfCU5ZI1g8LR3i2To3w0dg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

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