SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e3660e8d9872d5f67aa14846eb253ea442371bc9ffdffebcb6b8359ed37c6bf9' 
  AND token = '+6RGJyKqBngSVQlCkATXrll19YBbwWqkz/kvO+cRdyk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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