SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6f9550e4684a79f46273a416844dfc9922a1055de97b4ca875df2caac78ef96a' 
  AND token = 'fhJEy2XHMjK7gTtJhw/vqj20I0Nq+uByF4vClT92p8E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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