SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '29cc0b242f407a00ddd5f5db365dc117f42c096f3d0f39c333d87a8dbeba9567' 
  AND token = 'WpzO1bEeeY1Ec/pQM6gEdSRPu3RDeuFHqq5IPpeygu0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}