SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '62c921288ecee274ba6cf79dfa6be38ef010a4dc7ae3fb9fec21c247518dc4b0' 
  AND token = 'vAW/N7ujfvmryqqCkx+LlH9ft4i/wVbmfYPTM+GnUAs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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