SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a207aac533bc95fa6079b8bab60ae1e1e1f2ccffeba13caa0b7087be0615fd9b' 
  AND token = 'mjKD2nQapoZ5d2bAxdHB1ITEQ/HKCSgihQVEKkBXOlo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00052

JSON explain

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