SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '171036c3fb6d2929964217f3ab6764764d885109b82be9ee585788ff13676531' 
  AND token = 'c+jLT/wnmwt3H/fVhKY8aCk3ZpgURI4AE/wrZhhQ3LE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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