SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fae2851505a1aecbe56eeffb5441d851e5620510cc0d188d7bf32351a121295a' 
  AND token = 'IpCYYqbyp2ggv6SYn/CzgbltQJnt7Vtx4ZKHj6mhs18=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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