SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0a1bf844f6c59c28458425bb4dc16faabd750a23a8b94ee5c2dcf547af6ee058' 
  AND token = 'YzAKYTtktpDSpa4lDJS1Ll/JxkOOdd/NNzaCZ/sW7cw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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