SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '2a370df053aa40dcf3f114cc83bbaf1d46326e03c29cf238bf5c551b1f1d2115' 
  AND token = 'yn6AqW5Q6JAxKWsJwdeV0RQFP56Cr7AAw7BuLE7FQz0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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