SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0ffc0058a203fdb9ccddf6e37d9eddfa46e45d8443b41805ea816976d2068f0a' 
  AND token = 'Rhd/V2JkKuF1/7qb05Xvp80GTOGu4xiisVHPifxLk4k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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