SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f4fd07e43e610a17e24726686701e04bb7eacc811e39699ad3b2324812cbc97f' 
  AND token = 'NtsWDHSEMZdT4EyH2wxRC2iWXFbU3XmnuLJLI0UGHhc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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