SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '2b7b9e2fd6344c1d7ab000a53a2bcc21feb18649b95af573602db138145b02e8' 
  AND token = 'moEk5q1UauwWMoE1SChvO4RJvgvbRP/FfVTrKi4jCfQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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