SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2c95b37a8a8dd5fa544dffe16673e9dcda27c8bd50f16f6f199458e30c9c4392' 
  AND token = 'f0K9k/BLJpGHlG7JjirVpg7zLQ+glpLkngNm4wC8CI8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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