SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '31c18f186026019538da340bc859ec3edc33a4b306a241da843a00ae923938a0' 
  AND token = 'DH0spNTgErlITYve2NODGWTbR/KCXdKhXF/NIOtXaJg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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