SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'e38a62675633cf1ee139651799b9aff7724adfa851b19af12e501be2fae5d08e' 
  AND token = 'PfUif+vByVVgYAyvaDhty67tnZ3CoSM0LEATWyJbze8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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