SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6f11f640f495a53e5e0879fa79d0c9b730453fdac58fba53b0ccbae969d51670' 
  AND token = 'EKHaNyr2vv55i/cqk5Pt32J+KKDfAylJErlORBruQYA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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