SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c3595127154d872afd0558e7639c7a537188927e7b5345a4d539f6ce0bdd96b5' 
  AND token = '5X0ikrd32QL4CIOivEK1IsXsimK/D5X03sFpkchvVbA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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