SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1171dd49c49fb4df90a381f38980803902e0c074b54ac5decd40ce8f547bc4da' 
  AND token = 'x1z1FfNFOwiZR+9YTlptfU4PxTF7zAMAlTRxhQEQLsE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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