SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0d62fbb7685884fb1f12afb91a60432a9442307be26c2d014533dac4e6e2027f' 
  AND token = 'yGbCSNjz6kGdQKZ7tdLzqgKJUBZG6aFyCvSbE3qofwE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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