SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5aedf624c2641c95ece36eabec56ce99ec9e0f66216f6e4da8367692f1293018' 
  AND token = 'vsSYMK1+3NCx/L35Aklyhv5omuGy024cqyU1IQizpOg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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