SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '6106223cdf82624076029643cdfa271c2bc970b8736958a257cedce622b976b0' 
  AND token = 'ojRMaifCvSjXbHbLR5HQ/zXOD6SAFnxOSpf0qp7GwXQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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