SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1cab714446f41edcd99f219d6791ec6eeed7b0ba7fcce251015c0587122d00d8' 
  AND token = 'JRsOVGwdETvvkyiLIgatwdbzT2JTedvPOWWr+cvtCkA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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