SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'bf3274331bc1396b6ec37423752d1ba17a62cf62ea1aa3982e099f08d1543352' 
  AND token = 'j90axb4E1Yr5n/2xi4Ih3jIyMgPx6SSdTdYg5XbJr98=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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