SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e5b9bf36758583f4a4a5bdb75adaadd5c9f9eb905c8eea209160df6397130872' 
  AND token = 'S3bjGuDpkyr0UMD3FyJpuBxZTsS3W7K03iVaa4/SsY8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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